Simplify the visitation of target expressions. No functionality change.

llvm-svn: 211707
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.cpp
index 10d068d..e4740c2 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.cpp
@@ -11,6 +11,7 @@
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCAssembler.h"
 #include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCObjectStreamer.h"
 
 using namespace llvm;
 
@@ -127,33 +128,6 @@
   return true;
 }
 
-// FIXME: This basically copies MCObjectStreamer::AddValueSymbols. Perhaps
-// that method should be made public?
-static void AddValueSymbols_(const MCExpr *Value, MCAssembler *Asm) {
-  switch (Value->getKind()) {
-  case MCExpr::Target:
-    llvm_unreachable("Can't handle nested target expr!");
-
-  case MCExpr::Constant:
-    break;
-
-  case MCExpr::Binary: {
-    const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
-    AddValueSymbols_(BE->getLHS(), Asm);
-    AddValueSymbols_(BE->getRHS(), Asm);
-    break;
-  }
-
-  case MCExpr::SymbolRef:
-    Asm->getOrCreateSymbolData(cast<MCSymbolRefExpr>(Value)->getSymbol());
-    break;
-
-  case MCExpr::Unary:
-    AddValueSymbols_(cast<MCUnaryExpr>(Value)->getSubExpr(), Asm);
-    break;
-  }
-}
-
-void PPCMCExpr::AddValueSymbols(MCAssembler *Asm) const {
-  AddValueSymbols_(getSubExpr(), Asm);
+void PPCMCExpr::visitUsedExpr(MCObjectStreamer &Streamer) const {
+  Streamer.visitUsedExpr(*getSubExpr());
 }